Photometric projector compensation is used in various fields such as entertainment, cultural heritage, and augmented reality. The purpose of photometric projector compensation is to adjust one or more projected images from a projector in order to account for variations in the characteristics from one projector to another, variations in projection surfaces (e.g., color, material, and/or texture), and the like. By compensating one or more images to account for variations the images reflected or transmitted from the projection surface may better correspond to a desired image.
Conventional techniques for projector compensation generally involve a radiometrically calibrated projector. Radiometric calibration for a projector is often a laborious and time consuming process. For example, a typical radiometric calibration requires a specific measurement device such as a spectoradiometer, a photometer or a radiometrically calibrated camera, and a calibration software to generate a mapping into a well-defined color space, for example having a linear response function, sRGB, or one described by a specific gamma curve. Most of these calibration software tools only allow to calibrate individual color channels, such as red, green and blue, but do not consider the potentially complex internal color mixing during calibration. These conventional calibration techniques typically require recalibration if there are any changes to the systems, such as any hardware changes, changing projectors, or the like. Further, recently high end projectors include advanced color processing software and hardware and are difficult to analyze as the processing within the projector is often a “black-box” and the details are not known to the user, making it more difficult to model the projector behavior in terms of unknown color-processing and color-mixing in order to compensate the images accurately. These conventional techniques, in addition to being time consuming and difficult to execute, also may lose image contrast and color artifacts may occur due to intensity saturation of the projector on dark surface pigments. In other words, these techniques do not typically work well when the projection surface has dark colors.
It is with these shortcomings in mind that the present invention has been developed.